Sorry to barge into a forum that is apparently very well-established.

About a year and a half ago, I decided to get a bicycle to commute to work. Didn't care what it was, but happened to be convinced to purchase a used EZ recumbent. I was quite happy with it.

Then, yesterday on the ride home, the two rods that allow the seat back to be angled (though I've only ridden with the back erect) snapped. Sheared all the way through on both rods while just riding down the street. Just before the place where the rods are welded to the seat frame.

My questions are:

- Has this happened to anyone else?

- How does one get a new seat frame/angle rods and are they expensive?

- Is there a way to repair it, especially if you're not a "handyman"?

- Is there an option that doesn't even have the rods at all--just a fixed, straight backed seat for my recumbent?

Thanks for y'all's help.

Here is a picture of what I'm talking about, since I didn't know the right terminology about the seat frame being broken, rather than the struts.

Wow, that's serious fatigue failure in the aluminum. You might be able to get somebody to weld it back together for you, but that doesn't erase the source of the problem, too much flex. Let me guess... you tried to bend it so that the seat back would become more upright (the pin is in the last hole, which leads me to believe you may have needed more extension), and as you learned, high strength aluminum alloys do not work like steel.

Other than welding or buying a new seat, your only other solution is to use fiberglass and epoxy to "wrap" the T-connections in an composite joint. But this is more complicated that welding it.

So, you're stuck buying a new seat. Probably the cheapest and simplest solution. And this time, get longer struts for it so that you can get the right upright extension.

:)ensen.

I'd remove the fabric and have a competent welding shop just TIG weld it - then have him add a couple of short braces to prevent future bending. Or, you could opt for a replacement seat back frame:

https://cgi.ebay.com/NEW-Sun-Recumben...QQcmdZViewItem

thanks for the comments.

I didn't bend anything to get the seatback more upright. I just never changed it from the original setting that it was in when I got it (which was as erect as it would go, I think).

Any idea why it would just snap--on both sides simultaneously?

Also, I hang my backpack (with a laptop computer and other stuff) on the back for my commute to and from work. Could that have been what "put it over the edge"?

Pushing against the seat back while pedaling put upward bending forces on both ends of the "U" shaped tube that broke off. The fault lays in negligent design - the "U" shaped tube needs to be braced to prevent bending, or angled downward slightly to reduce bending forces on the joints that broke.

No. The added weight is supported by the struts and puts no significant stresses on the joints that fractured.

{EDIT} Correction; After looking at a side view, if you mount your load (laptop, stuff, etc) on the upper most, horizontal member (not the lower, horizontal member that broke (and shown in your image)), then yes, the added weight will increase the bending forces on the member that broke. However, mounting your load on the lower, 'broken' member (after the repair or replacement, of course) and you'll be fine because the load will then be primarily supported by the struts (aka, seat back braces) and not the seat back.



Question: Is this an EZ-1? And do you have the seat adjusted all the way aft?

I'm afraid I wouldn't know if it's an EZ-1. How can I tell? The seat is pretty far back, possibly at the extreme position.

As to the backpack, I hang it on the "shoulders" of the seat back.

Thanks for the help.

Easy Street Recumbents (online catalogue, call to order) will have the parts you need if you don't get it on ebay. I would talk to them about which seat backs will fit your bike because some of them have vertical braces supporting the U tube. bk

EZ-1 has a 20" rear wheel and a 16" front. The EZ Sport has 26/20 wheels.

I would discourage mounting anything much above a couple of pounds in the red "A" area. The green "B" area (where the struts are bolted) can withstand much heavier loads.

You know, with the seat so upright, you may in fact be putting all your backward force near the shoulders, causing flex right at the point where the seat broke. A couple of questions...

1) Is the seat distance to the pedals correct? Within no more than about 1-1/2", the bottom of the seat back should be the same distance to the most forward part of the pedal stroke as your X-seam. X-seam is the distance from the wall to the balls of your feet when you sit flat against a wall.

2) Are you pulling and pushing on the handlebars during the ride? Doing so varies the forces you place on your shoulders and thus the top of the seat back. This may also fatigue the handlebars so much they also break.

:)ensen.

Just go here and look at the models. Since Easy Racers most likely designed your bike, they may have an idea of what "could" have caused the break.

https://www.easyracers.com/

Another question would be, are you a pretty good sized guy?

I doubt that putting a backpack or seat bag on the top would add enough of a load to have mattered; what really caused the breaks was repeated stress/bending at those spots. Pushing extremely hard on the seatback could have done it, or repeatedly picking up the bike by the cross-bar could have done it. At any rate, I haven't heard of this type of failure being common; so it's probably something peculiar that you're doing to it. The best permanent solution would be to find a home builder or handyman who has a brazing setup, and have them fabricate a replacement out of thin-walled chromoly using the original as a pattern. 1/2" x .035 Chromoly wouldn't weigh that much and would be a better material for a seat back.

This is the second one I know of - both were aluminum frame and both had the seat adjusted furthermost aft, thus generating an acute angle at the seat strut/seat back. Look at the picture I posted. Mounting a heavy load at the top of the seat back exacerbates the problem, especially when riding on rough surfaces. Take a look at the newer (2009) seats and you'll notice that an additional vertical brace (running the entire length of the seat back) was added which prevents this problem.

hmm... I see what you mean.


That'd work. Bottom line is, aluminum can't be allowed to flex or it will break. Steel still has a finite life cycle, but it's much higher than aluminum. I think the (old) broken seat was originally designed by Gardner as a steel structure. When Sun took over, they should have kept making them out of steel or redesigned them immediately.

I wonder if Randy sent a query to Sun, if they'd treat it as a warranty issue -- after all, redesigning the frame is pretty much an admission of a problem. Even if they don't offer a free replacement, he might get a 'good price' on it.

This site is a wealth of information. Thanks to all.

Based on the explanation, I must have an EZ Sport, as I have 26/20 inch wheels. I contacted the bike shop that has the eBay listing and they tell me the seat they're selling is steel. I think I'm going that rout, rather than trying to find someone who can fabricate a seat for me.

I really don't know about exact measurements, but I think the seat is the right distance from the pedals, as determined by the bike shop guys (Touring, Tandems, & Recumbents of Greenville SC). I don't put a lot of stress on the handlebars, because they will move some if I do (my main complaint about the bike is that you just can't tighten them enough to be fully secure in place). As to the amount of stress I put on the seat as I pedal, I can't imagine any way of reducing that pressure and still being comfortable riding the bike. In fact, when I had to ride it the rest of the way home on the day it snapped, I noticed just how much I "slide" back as I pedal without that support to keep that from happening. I just can't see how I'd get any force on the pedals if I didn't have some pushback on the seatback.

Anyway, I only ride about 5.5 miles each day on the commute, all on city streets, so I'm hoping the all-steel replacement will work out for me. The bike shop guy in Florida (eBay sale) tells me it lists for $95, so I figure $45 is a reasonable deal (plus shipping) and then I'll have a lot of other extra parts around should some of the other pieces fail.

Steel replacement seat frame sounds like the way to go.
I would be looking for a way to secure your handlebars. That sounds like an issue - that you are already aware of.

I seem to remember some handlebars not tightening fully being an issue on a bike before, but can't remember which brand.
On my recumbent I don't really push back on the seat as much as I spin the pedals. No pulling on the handlebars either, but they shouldn't move in the stem if you do. If the bar is too small for the stem to properly clamp it, then maybe a metal shim in there might work.

The Earlier Suns had an issue with handlebars slipping. I think there was a fix - a shim or something. It might pay to ask on the EasyRacer forums. A steel seat back for $40 sounds like a win-win deal.

Randy, (and other EZ owners),

Here's a parts break-down of most of the earlier EZ products (Took me a while to find it again). You can compare different parts, including which are steel or aluminum. and what models they're found on.

https://www.bicycleman.com/files/Sun-...ccessories.pdf

And FYI, if you need individual EZ parts in the future, you might try here:

https://74.8.32.132/nondealer/view.ph...rand_key=44266 JB Importer

or here:

https://bethelcycle.com/page.cfm?PageID=271 QBP

... grab the part# and call your local bike shop (LBS) as most have either JB Importer's or OBP's catalogs and they can order it for you (often without shipping cost if it's included in their regular order).

Randy, give these guys a try as well. I have been doing business with them off and on for a few years when it comes to replacement parts for my Vision R40. They have never steered me wrong in advice or the correct part; https://www.hostelshoppe.com/

Thanks again for all the help. The replacement back frame arrived (from the eBay purchase) on Saturday and I replaced the broken one yesterday (Sunday). The new one is noticeably heavier and does have the extra two vertical rods for support. Hopefully this one will last a long while.

I did contact bjimporters (via one of the links above--maybe the easyracers.com reference) and they asked for more pictures so they could check to see if it is a warrantable issue. I can't see that being the case, since I purchased it used, but if they come back and refund my money, that's even better. Either way, I'm happy to be back on the bike.

It may have been a product recall. Using aluminum in a way that does not account for the specifications of the metal could be considered a manufacturers defect. That your replacement and indeed all new seats seem to have the extra struts may be proof that a design change was made. Seems to me it's a common way for a manufacturer or distributor to rectify a known issue without admitting liability.

:)ensen.

I can offer no advise on the seat, but welcome to the forums. This truly is the best place for REAL cycling info.